Block motion estimation

摘要

Methods and apparatus for conducting motion searching are provided. A first 2D array includes interconnected multi-directional shift registers for storing and shifting image values corresponding to a search window within a search region. A second 2D array includes registers for storing image values corresponding to a macroblock. A distortion calculation module is arranged to calculate and output a distortion value corresponding to the difference between image values stored in associated registers of the first and second arrays. The distortion value quantifies the correlation between the search window and the macroblock. The shift registers of the first 2D array are controlled to pass image values between adjacent shift registers to translate the position of the search window within the search region. Distortion values outputted after progressive shifts of the first 2D array are tracked to determine an optimal registration position of the macroblock relative to the search region.

主权项

1. A digital processing apparatus suitable for use in video encoding, the apparatus being arranged to conduct motion searching by comparing an image macroblock against a plurality of positions within an image search region, the apparatus comprising:
a first 2D array comprising interconnected multi-directional shift registers for storing and shifting image values corresponding to a search window within the search region; a second 2D array comprising registers for storing image values corresponding to a macroblock; a distortion calculation module operatively connected to the first and second 2D arrays, the distortion calculation module being arranged to calculate and output a distortion value corresponding to the difference between image values stored in associated registers of the first and second arrays, the distortion value thereby quantifying the correlation between the search window and the macroblock; wherein the apparatus is arranged, in use:
to control the shift registers of the first 2D array to pass image values between adjacent shift registers to translate the position of the search window within the search region; andto track distortion values outputted after progressive shifts of the first 2D array thereby determining an optimal registration position of the macroblock relative to the search region; a time budget management module for controlling at least the number of shifts carried out by the first 2D array so as to manage the time spent performing each motion search operation; and a seed list generator for generating a prioritized list of seed search regions against which a macroblock is to be searched, the seed list generator being arranged to down-sample a video image frame and a macroblock, feed the down-sampled video image frame and macroblock into the first and second 2D arrays to conduct a motion search operation and thereby determine a prioritized list of seed search regions within the original image frame against which the original macroblock may be searched, wherein the time budget management module is operatively connected to the seed list generator to receive a prioritized list of candidate search regions from the seed list generator.